1. Field of the Invention
The present invention relates generally to a device used for measuring fluid level in a large container or tank and, more particularly, to devices used to remove any fluid remaining on the measuring device.
2. Description of the Prior Art
The storage of oil, gasoline or other liquids in large tanks is commonplace. Many of these tanks are buried underground and many do not have fluid level gauges. Therefore, to determine the amount of fluid left in a tank one end of a “dipstick” is inserted into the top of the tank until it reaches the bottom of the tank at which point the stick is withdrawn. At least some of the fluid in the tank adheres to the stick. The level of fluid in the tank is determined according to the height on the stick to which the liquid adhered. Then the fluid must somehow be removed from the stick in order to avoid staining the stick, creating a mess, and, more importantly, to substantially eliminate both fire and environmental hazards which might otherwise result.
In the past, rags have been used to clean these dipsticks and are still used by many today. However, the oil or gas soaked rags pose environmental and fire hazards and their disposal can be problematic. In addition, the purchase of these rags when used in conjunction with frequently measured and large tanks can be expensive.
Devices have been designed to assist in the cleaning of dipsticks although most are specifically intended to be used to check oil levels in combustion engines rather than liquid levels in large tanks. To that end, there are hand-held devices which operate similarly to tongs such that a cleaning pad is mounted on each jaw of the tongs. To clean the dipstick the tongs are opened and the dipstick positioned between the jaws; then the tongs are closed and the stick drawn upwardly. Liquid is removed from the dipstick by the cleaning pads. (See U.S. Pat. No. 4,233,704). Others simply provide a slit in a flexible cleansing material into which the dipstick is slid and then drawn upward.
A number of dipstick squeegees (more particularly designed for engine oil checking) are constructed such that they are attached to the dipstick tube or otherwise mounted on the engine. For example, see U.S. Pat. No. 5,598,602 which employs a squeegee device mounted on the engine which includes a swing arm. The arm is swung into position so that the dipstick can be placed between two sides upon each of which is mounted a disposable cleaning pad. The sides are then squeezed together while the stick is drawn upwards and the liquid removed. The same general idea without the swing arm is disclosed by U.S. Pat. No. 4,716,615 where the device is mounted onto a dipstick receiving tube.
Another example is disclosed by U.S. Pat. No. 4,891,859. Here again the device is mounted on the engine compartment and includes a semi-circular vertical channel with two pairs of vertically spaced resilient flaps inside. The dipstick is moved into the open side of the semicircular channel and between the flaps and drawn upward to remove liquid.
None of these inventions is easily or effectively adaptable to use for measuring liquid levels in large tanks which store, for example, gas or oil. These tanks are often filled though the same opening as their levels are checked which means that the dipstick is not resident there when not in use. Therefore, those prior inventions which combine the stick with a device intended to remain mounted on the tank could create an obstacle to efficiently filling the tank.
There are a few ideas adapted to use for the large-scale tanks. For example U.S. Pat. No. 4,282,624 discloses a device which is attached to the collar or opening of the tank and includes a rubber plat with a slit which is protected on at least three sides by a metal plate. This device is resident with the tank. The slit design is relatively short lived as many of these dipsticks are of cross-section dimensions which do not fit particularly well into the slit. If the slit is widened, parts of the stick will not be contacted leaving fluid on the stick. None accommodated the varying shape of a strapper which is a retractable tape having plum bob at one end.
These large tanks are often filled and levels consequently checked by drivers of tanker trucks. The oil or gas or other liquid remaining on a dipstick or on a tape when checking tanks of this size is, of course, much greater in volume than that on a car engine's dipstick. Therefore the number of rags and the environmental hazards they pose are increased exponentially. It is not reasonable, then, to use any prior inventions wherein absorbent pads are employed. Additionally, the drivers of tanker trucks may deliver at a number of different places so they need a squeegee that is light, transportable, and durable with a wiping surface that is also relatively durable but also easily replaceable when worn. They cannot depend on the places to which they deliver to maintain or even have an efficient squeegee device. The squeegee must be chemically resistant to erosion and sturdy enough to withstand use with dipsticks or tapes with a plum bob up to ten feet long and 1 to 3 square inches in cross section or diameter. Because of the sheer size of these dipsticks and tapes, a handheld squeegee is not practical; one must be able to maneuver the stick or the tape which typically requires both hands.
What is needed is a light and easily transportable, but durable squeegee device which deposits fluid adhering to the dipstick or the tape and plum bob back into the tank. It is desirable to avoid absorbent pads and their consequential environmental and fire hazards and design instead a squeegee that includes a durable surface to remove the liquid which surface can be simply and easily replaced as needed. Although the device needs to be easily transportable and storable, it must also be of a size and construction to survive the rigors of being used with large dipsticks or long tapes. The device must be able to accommodate the varied shapes of a tape and plum bob and able to clean the surface of each. If preferred, the device must be adaptable to be detachably affixed to the collar of tank while leaving a space between the wiper member and the collar through which a measurement of liquid level can be observed. Finally, while light and transportable, the squeegee needs to be constructed for hands-free use and resistant to chemical erosion by gasoline and oil products.